1. Field of the Present Invention
The present invention relates to a film deposition apparatus.
2. Description of the Related Art
Conventionally, as disclosed in Japanese Laid-Open Patent Application Publication No. 2013-118411, a turntable-type film deposition apparatus using ALD (Atomic Layer Deposition) or MLD (Molecular Layer Deposition) is known. The film deposition apparatus includes a turntable capable of receiving a plurality of substrates along a circumferential direction of the turntable in a vacuum chamber, and a first reaction gas supply part and a second reaction gas supply part provided apart from each other in a rotational direction of the turntable. In ALD and MLD, a thin film is deposited on surfaces of the substrates by supplying a first process gas and a second process gas that are reactable with each other from the first reaction gas supply part and from the second reaction gas supply part in series, respectively, to the surfaces of the substrates, and by repeating this supply cycle so as to deposit a reaction product of the first reaction gas and the second reaction gas in a layer-by-layer manner.
In a film deposition apparatus disclosed in Japanese Laid-Open Patent Application Publication No. 2013-118411, at least one of a first reaction gas supply part and a second reaction gas supply part is configured to be an activated gas injector. The activated gas injector includes a flow passage formation member dividing a flow passage into a gas activation flow passage and a gas introduction flow passage by a partition wall, a gas introduction port for introducing a process gas into the gas introduction flow passage, and a pair of electrodes provided extending along the partition wall in parallel with each other in the gas activation flow passage and configured to receive electricity to activate the process gas. The activated gas injector further includes communication holes provided in the partition wall along a lengthwise direction of the pair of electrodes to supply the process gas in the gas introduction flow passage to the gas activation flow passage, and gas discharge holes provided in the gas activation flow passage along the lengthwise direction of the electrode in order to discharge the process gas activated by the gas activation flow passage.
In the above-mentioned turntable-type film deposition apparatus, because a moving speed of the turntable during one revolution differs at the central side and the peripheral side, an adsorption amount of the process gas on the plurality of substrates placed along the circumferential direction of the turntable differs at the central side and the peripheral side, which sometimes has a negative impact on uniformity of a film deposited on the substrates across the surfaces of the substrates. However, the uniformity of the film across the surface of the substrate can be improved by using the activated gas injector disclosed in Japanese Laid-Open Patent Application Publication No. 2013-118411 because the activated gas injector can distribute the supply of the process gas. More specifically, by controlling concentration distribution of the process gas and a period of time of contacting the process gas, the process gas is caused to uniformly adsorb on the substrate across the surface and the uniformity of the film thickness across the surface of the substrate can be made preferable. Moreover, for example, when there is a demand of film deposition under high pressure conditions, the uniformity of the film thickness across the surface of the substrate can be controlled by supplying a large amount of carrier N2 gas to the process gas so as to increase a flow rate of N2 in order to adjust displacement of the process gas in the activation gas injector.
However, when there is a demand of film deposition under further higher pressure conditions in the future, the flow rate of carrier N2 gas is increased for the gas displacement to respond to the demand, but such a response has limitations because the increase of the supply of N2 gas causes the decrease of the activation of the process gas to be supplied to the substrates.